I haven’t read all the posts here yet so maybe someone already suggested this. I still think you are an artist you just have what is similar to ‘writers block’ only it’s ‘quilters block’ (no pun intended :-P ) You said you want your design made of squares and triangles. How about drawing it out on graph paper, it’s a start and the ideas may just start coming to mind. You’ll see what you like and what you don’t like and keep it or eliminate it – your ideas may grow and change as you do this.